NASA Scientist Amitabha Ghosh says, "If you were staying for six months on the moon, you could drink a litre of water a day, you could extract oxygen, use it as a fuel for a return journey."

The question however is, how did this water get on the moon?

A new theory suggests protons - the smallest particle inside hydrogen atoms - travel to the moon from the sun. On striking the soil, they react with the oxygen trapped in it to form water. However, scientists say water does not mean that there is life on the moon.

Senior Scientist, Indian Institute of Astrophysics, Professor C Shivaram says, "The moon has no atmosphere. Extreme conditions would have killed the most primitive life. Don't expect life at all."

Nonetheless, scientists say with water on the ground, humans could eventually colonize the moon. And since launching rockets from there would be 20 times cheaper than launching from earth, the moon could be our gateway to outer space.